1. Field of the Invention
This invention is generally directed to distillation equipment which utilizes solar energy to separate the chemical components of an original product and more specifically to a process of waste control management wherein solar energy is utilized to obtain non-hazardous byproducts from contaminated waste materials by retaining such materials in solar drying units wherein the materials may be exposed over long periods of time to elevated temperatures caused by the sun's radiation so as to effectively drive substantially all of the hazardous and more volatile components from the material and reclaiming such components in a purified state as liquid distillates which can be thereafter reused in an industrial capacity. Also, the residue remaining within the solar dryers are substantially free of contaminants and therefore can be classified and handled as non-toxic byproducts which may be reworked for future industrial use or disposed of in conventional disposal sites. The process and apparatus have particular use in various industries such as wherein acetone is utilized in a manufacturing process in combination with binders, fiberglass and other fillers. The hazardous waste materials from such processes, including the acetone, can be treated with the acetone being purified and recaptured for commercial use. The residue of the waste material is also capable of being reworked as a non-hazardous product with potential uses and as binder resin material. The process of the present invention can be practiced without the requirement for the input of any electrical or other outside sources of energy other than that naturally occurring from the sun.
The processes and apparatus of the present invention thereby make it possible to eliminate the need for costly and environmentally hazardous waste disposal sites to be established for handling toxic wastes by enabling such wastes to be separated by distillation and drying and subsequently recycled for industrial uses without leaving any residual toxic wastes.
In one form of the invention, the solar drying apparatus are mounted within concrete containment supports which are designed to allow flow by gravity through a plurality of solar drying units or chambers so that any contaminated liquids which are pumpable may be passed through the system and introduced to the drying units with the purified distillates being discharged therefrom in a manner which requires no electrical input to maintain a flow through the system thereby further reducing costs of recycling the various components of the hazardous waste materials.
2. History of the Art
There is an evergrowing awareness not only in the United States but in other countries of the effect that chemical dumping is having upon the environment not only locally but generally. Ground water supplies are increasingly becoming contaminated through the dumping of chemicals used in manufacturing, chemical processing, oil spills, gasoline leaks and from improper chemical handling and the like. Many such hazardous chemicals are introduced involuntarily into the ground and after a period of time begin to contaminate the local water supply. After prolonged periods of time, the pollutants are spread over larger areas as hazardous chemicals are carried by subsurface waters to other areas. In addition to the foregoing, it is common practice even though illegal for many manufacturers to discharge chemical waste byproducts of manufacturing processing by illegal burial or dumping activities. Such activities have led to contamination of local land sites, local water sources and larger areas such as rivers, bays and even ocean water.
In more recent years, governments have begun regulating the disposal of various types of hazardous or contaminated waste materials. However, with regulation comes the necessity for enforcement and such enforcement is often difficult especially when trying to regulate the disposal of the lower level chemical toxins which are frequently used in a plurality of industries. Such chemicals include various solvents, oils and other products including acetones, methylene chlorides, trichloro-ethanes, halogenated hydrocarbons such as known by the trademark FREON, and the like.
Until recently, many of the foregoing chemicals were simply disposed of by dumping or by allowing liquid components to evaporate and thereafter discharging or dumping of the sludge material which remained. Newly enacted regulations, however, are requiring that manufacturers account for the handling and disposal of such manufacturing wastes. In an effort to meet government regulations and to preserve the environment, many manufacturers have had to result to processing chemical waste in an effort to reduce the amount of waste material and then have had to utilize special waste disposal sites for the disposal of the residual hazardous materials left from such processing. Such toxic waste management handling has proven to be economically burdensome and in the long run wasteful of products and materials.
Currently, there are several types of commercially available processes for recovering solvents. Such processes involve the use of thin film evaporators or electrical batch processing stills. In a commercial batch processing system, energy is supplied to a batch of waste material and the volatile components are boiled off until such time as a residual sludge remains within the processing still. Thereafter, the material is removed from the still and prepared for an appropriate disposal. It should be noted that the waste material which remains as sludge is considered hazardous and toxic waste and must be handled as such, and therefore, the eventual costly storage or burial of the sludge waste material is not eliminated.
In thin film type evaporators, the toxic material is sprayed in the middle of a jacketed tube which is heated by steam. As vapor comes off, residue remains on the walls of the unit where it is scraped from the walls as a residue. The remaining residue like that of the batch processing stills remains classified as a toxic or hazardous waste material and again must be handled in accordance with government regulations for the disposal of hazardous wastes.
It is commercially not profitable to utilize conventional solvent recycling or recovery processes due to the fact that there remains a waste residue which must be handled as a hazardous material. Any efforts to further distill the volatile components within conventional processing units would require enormous inputs of energy which are overly costly and not practical. In essence, energy input into an electric or steam distillation process is not effective if it is desired that all the solvent be driven from the residue. Such systems may be practical when removing approximately 90% of the solvent, however, the energy to remove the remaining 10% would require two to three times additional energy input and thus are cost prohibitive.
The use of solar energy in distilling various chemical components is well known. Utilizing the sun's energy, it is possible to drive one volatile component from a less volatile component and thereby separate materials into two separate constituents or byproducts. Such uses are currently being made of solar stills in the recapture of fresh water by the distillation of salt water. There has not been, however, any suggested use of solar energy for eliminating the hazards of chemical waste disposal. Further, it has not been proposed to utilize the sun's energy in a process whereby hazardous waste material is not only separated through solar energy but where the solar energy is used to dry portions of the materials to a point where the residues which remain are no longer considered as hazardous wastes. Therefore, it has not been recognized that solar energy can be used to enable potentially hazardous wastes to be handled and recycled without waste and without the need for additional hazardous waste handling, treatment or storage.
Some examples of prior art solar distilling equipment are disclosed in U.S. Pat. Nos. 2,342,062 to Schenk; 2,424,142 to Bimpson et al.; 2,975,107 to Friedman; 4,135,985 to La Rocca; 4,159,228 to Bellande; 4,209,363 to Ramer; 4,371,623 to Taylor and 4,495,034 to Lucas. Only the reference to Lucas is concerned with the treatment of waste effluents to recover solvent.